user.rb

class User < ActiveRecord::Base
  # Include default devise modules. Others available are:
  # :confirmable, :lockable, :timeoutable and :omniauthable
  devise :recoverable, :rememberable, :trackable, #:validatable,
         :omniauthable, :omniauth_providers => [:steam]
         #:database_authenticatable, :registerable,
  
  def self.from_omniauth(auth)
    where(steam_id: auth.uid).first_or_create do |user|
      user.steam_id = auth.uid
      user.steam_username = auth.extra.raw_info.profileurl.split("/").last   # assuming the user model has a name
    end
  end
end